Aromatic polysulfones are a known class of polymers which are thermoplastically processable. These materials have a major drawback in their tendency to be soluble in several solvents such as chloroform, methylene chloride, cyclohexanone, cresol, and hydraulic fluids. This solubility causes components which are fabricated from these polysulfones to be susceptible to damage by these solvents, and therefore, precludes use of this polymer system for many applications.
Aromatic polyimides, conversely, are a class of polymers which are generally considered not to be readily processable via thermoplastic techniques, but exhibit exceptional resistance to solvents.
Both the aromatic polysulfones and aromatic polyimides have good thermal stabilities with the use temperatures thereof being generally governed by the softening temperature of each system.
There is thus a definite need in the art for a solvent resistant polysulfone and a thermoplastic polyimide which can be used as a molding compound, as an adhesive, and as a resin for the fabrication of fiber reinforced composites.
Accordingly, an object of the present invention is to provide a solvent resistant aromatic polysulfone.
Another object of this invention is to produce a thermoplastic aromatic polyimide.
Another object of this invention is to make a thermoplastic, solvent resistant polymer which can be utilized as a molding resin.
Another object of this invention is the production of a thermoplastic, solvent resistant polymer which can be utilized as an adhesive.
Another object of this invention is to provide a thermoplastic, solvent resistant polymer which can be utilized as a matrix resin for fiber reinforced composites.
Another object of the present invention is a process for thermoplastically forming moldings, adhesive bonds and fiber reinforced composites from solvent resistant aromatic polysulfones.
An additional object of the present invention is a process for combining two high temperature polymer systems to retain the advantageous properties of each while minimizing or eliminating the disadvantages thereof.